1. Technical Field of the Invention
The present invention relates to a light source unit and a projector system including the light source unit, and more particularly to a light source unit which enables the installation of a number of LED's therein as light sources and which is made small in size by increasing the utilization efficiency of light emitted from the LED's so installed and a projector system including the light source unit.
2. Description of Related Art
While many high pressure mercury lamps were used in light sources for projector systems, the high pressure mercury lamps had problems of large power consumption and short lives. Due to this, in recent years, light emitting diodes (LED's) have been in use instead due to small power consumption and long lives, as well as low heat generation, which less affects peripheral equipment.
FIG. 7 is a schematic diagram which illustrates an example of a conventional projector system including a light source unit which uses LED's as light sources. A light source unit 31 provided in a projector system 30 is made up of a long transparent quadrangular prism-shaped mirror tunnel 32 and a light source 33 provided at one end of the mirror tunnel 32 which is made up of red, green and blue LED's. The LED's in the respective colors which make up the light source 33 are arranged in arrays.
A lens 34 is provided on an optical axis K near the other end of the mirror tunnel 32 where the light source 33 is not provided.
A reflector 35 is disposed on the optical axis K in a direction in which light emerging from the lens 34 travels in such a way that a surface of the reflector 35 which is to be illuminated by light so traveling is angled at a predetermined angle relative to the optical axis K.
A micromirror device (a Digital Micromirror Device or DMD) 36 is disposed on the optical axis K in a direction in which light is reflected by the reflector 35. A projection lens 37 is disposed on the optical axis K in a direction in which light is reflected by the micromirror device 36. The projector system 30 is adapted to project an image by causing the respective red, green and blue LED's to emit light in the relevant colors in accordance with color indications by the micromirror element 36 for split indication of the respective colors.